IT'S TIME TO SMELL THE FLOWERS IN NATION'S GARDENS.

Byline: Jerry Morris Boston Globe

It's blossom time again. The flower show season is upon us, and whether you have a green thumb or not, it's a great time to think spring.

The 49th annual Spring House and Garden Tour in Charleston, S.C., takes place March 21-April 20 and offers visitors the opportunity to experience the private side of Charleston. For information on events - every day there is a new tour - call [phone]. Delta is offering special discounted rates to the festival; call [phone] and ask for file number L0544.

"America's Largest Open House" - a tour of homes and gardens - takes place April 20-21 in Virginia. More than 250 of Virginia's most beautiful properties will be featured in the annual event of the Garden Club of Virginia. For a brochure listing dates and localities of garden week tours, write: Historic Garden Week, 12 E. Franklin St., Richmond, Va. 23219; or call: [phone]. For a 200-page guidebook, enclose $3 for postage. For travel and accommodation information, call the Virginia Division of Tourism at [phone].

Colonial Williamsburg will hold its 50th annual Garden Symposium April 14-17. For information, call [phone].

Other flowering events to keep in mind include New Zealand's largest floral and garden show, April 10-14. New Zealand, known as a gardener's paradise, will hold the show in conjunction with the World Association of Flower Arrangers. Information: [phone].

Always a special place, Nantucket blossoms during its annual Daffodil Weekend, April 26-28. Among places to stay or dine is the Summer House, which has a collection of fishermen's cottages filled with antiques. Information: [phone].

The fifth annual hidden garden tour of the Westport, Conn., Historical Society will be held June 7-9. Information: [phone].

April also brings fantastic glacial flowers. Some of the nation's best wildflower viewing can be found in Glacier National Park in northwest Montana. Wildlife and nature photographers will find a paradise of alpine meadows filled with glacier lilies, bear grass and spectacular purple silky lupines and astors. There's also an abundance of wildlife. Call Glacier Park for information on tours and lodging, [phone].

If you are heading for England, take in the Privy Garden of 1702 at Hampton Court in southwest London. The garden, considered the most important restoration project in British gardening history, was opened last summer. Until the 1890s, the garden was reserved for the exclusive use of either the monarch or selected courtiers.

There are also lots of garden tours. Some of Ireland's loveliest gardens are included in a 13-day tour June 3-15 by Coopersmith's England. Coopersmith's also is offering tours to Portugal gardens, May 6-17, and West County Gardens and the Chelsea Flower Show in England in May. For informaion, write to Coopersmith's, P.O. Box 900, Inverness, Calif. 94937; telephone [phone].

Expo Garden Tours will have a tour of Holland at Tulip Time, April 18-27. For information, write to 101 Sunrise Hill Road, Norwalk, Conn. 06851; or call [phone].

In the English Manner offers 15 tours on the British isles that feature private gardens and stays in country manor homes and castles. All the packages are from $1,750 to $2,499 a couple and include many meals and a midsize rental car. Information: [phone].